ES2771900T3 - Valve-sleeve fixings for prosthetic heart valve - Google Patents

Abstract

A prosthetic heart valve, comprising: a stent (302) having a collapsed condition and an expanded condition, the stent having a proximal end, a distal end, and a plurality of commissure features (316), wherein the prosthetic heart valve also includes; a valve assembly (304) attached to the stent, the valve assembly including a sleeve (306) and a plurality of leaflets (308), each leaflet having a free edge extending between a first end attached to one of the plurality of commissure features and a second end attached to another of the plurality of commissure features, and a second edge attached to the sleeve, the second edge having a first end, a second end, a first folded portion adjacent to the first end, a second folded portion adjacent the second end, and a portion deployed between the first and second folded portions, the first and second folded portions engaging the leaflet to one of the commissure features; and a backing disposed along the deployed portion of each of the leaflets, the backing comprising a back stitch, the back stitch having a repeating triangular pattern.

Description

DESCRIPTION

Prosthetic Heart Valve Cuff Fixings

Background of the invention

The present invention relates to the replacement of a heart valve and, in particular, to collapsible prosthetic heart valves. More particularly, the present invention relates to collapsible prosthetic heart valves having single valve leaflet attachments.

Prosthetic heart valves that are collapsible to a relatively small circumferential size can be inserted into a patient less invasively than valves that are not collapsible. For example, a collapsible valve can be introduced into a patient by means of a tube-shaped introduction apparatus, such as a catheter, trocar, laparoscopic instrument, or the like. This folding ability may avoid the need for a more invasive procedure, such as a complete open-chest and open-heart surgery.

Foldable prosthetic heart valves are typically in the form of a stent-mounted valve structure. There are two common types of stents in which the valve structures are normally mounted: a self-expanding stent and a balloon-expandable stent. To place such valves in a delivery apparatus and ultimately in a patient, the valve may first be folded or wrinkled to reduce its circumferential size and diameter.

When a collapsed prosthetic valve has reached the desired implant site in the patient (for example, at or near the annulus of the patient's heart valve to be replaced by the prosthetic valve), the prosthetic valve can be deployed or released from the supply apparatus and re-expand to full operational use range. For expandable balloon valves, this generally involves releasing the entire valve, securing its proper position, and then expanding a balloon placed within the valve stent. For self-expanding valves, on the other hand, the stent automatically expands as the sheath covering the valve is removed. US2012 / 123529 describes a prosthetic heart valve. US2008 / 071361 describes a leaflet responsive valve fixing member. EP2572676 describes collapsible prosthetic heart valves. US2011 / 319991 describes a low profile transcatheter heart valve. WO2014 / 004793 describes a leaflet configured to function in various shapes and sizes.

Brief summary of the invention

The invention is defined by the appended claims. In some embodiments, a prosthetic heart valve includes a stent that has a collapsed condition and an expanded condition, the stent has a proximal end, a distal end, and a plurality of commissure features characterized in that the prosthetic heart valve further includes; A valve assembly secured to the stent, the valve assembly includes a sleeve and a plurality of leaflets, each of the leaflets having a free edge extending between a first end attached to one of the plurality of commissure features and a second end attached to another of the plurality of commissure features, and a second edge attached to the sleeve, the second edge has a first end, a second end, a first folded portion adjacent to the first end, a second folded portion adjacent to the second end, and a deployed portion between the first and second folded portions, the first and second folded portions couple the leaflet to some of the commissure features; and a gusset disposed along the deployed portion of each of the leaflets, the gusset comprises a reverse stitch, the reverse stitch has a repeating triangular pattern.

In some embodiments, a prosthetic valve assembly includes a substantially cylindrical sleeve, a plurality of leaflets disposed within the sleeve, a reverse stitch coupled to deployed portions of each of the leaflets, the reverse stitch having an outer portion disposed between the cuff and each of the leaflets and an inner portion disposed on an opposite side of each of the leaflets and a suture for coupling the sleeve to each of the leaflets.

Brief description of the drawings

Various embodiments of the present invention are described herein with reference to the drawings, wherein:

Figure 1A is a partial side view of a prosthetic heart valve showing a possible strain distribution profile of the valve assembly;

Figure IB is an enlarged partial view of the prosthetic heart valve of Figure 1A showing the distribution of deformations in the leaflet;

Figure 2A is a highly schematic cross-sectional view of a portion of a collapsible prosthetic heart valve in accordance with the present invention having folded leaflets sutured to the cuff;

Figure 2B is an enlarged side view of a portion of a collapsible prosthetic heart valve in accordance with the present invention showing a folded ventral crease;

Figure 3 is a developed partial view of a collapsible prosthetic heart valve in accordance with the present invention showing the pattern of suturing the leaflets to the cuff;

Figure 4 is an enlarged side view of a portion of the collapsible prosthetic heart valve of Figure 3 showing the region of the slider between anchors;

Figures 5A and 5B are side views of a collapsible prosthetic heart valve according to the present invention having a tissue bag between the cuff and the leaflet, and a prior art device lacking such a bag, respectively;

Figure 6 is a partial side view of a prosthetic heart valve showing the cuff-leaflet fixation load distribution of the valve assembly;

Figure 7A is a highly schematic perspective view of a ring secured to a sleeve;

Figure 7B is a highly schematic top view of a ring secured to a sleeve;

Figure 8 is a side view of a collapsible prosthetic heart valve having a ring;

Figure 9A is a side view of another collapsible prosthetic heart valve having a ring;

Figure 9B is an enlarged side view of a portion of the collapsible prosthetic heart valve of Figure 9A showing the cross struts of the rings;

Figure 10A is a highly schematic cross-sectional view of a portion of a collapsible prosthetic heart valve in accordance with the present invention having a folded leaflet sutured to the collar and cuff;

Figure 10B is a highly schematic cross-sectional view of a portion of another collapsible prosthetic heart valve in accordance with the present invention having a folded leaflet sutured to the collar and cuff;

Figure 10C is a highly schematic cross-sectional view of a portion of another collapsible prosthetic heart valve in accordance with the present invention having a folded leaflet sutured to the collar and cuff;

Figure 11A is a side view of a leaflet folded over to produce a ventral crease secured by a reverse stitch;

Figure 11B is a highly schematic cross-sectional view of a portion of another collapsible prosthetic heart valve in accordance with the present invention having a folded leaflet sutured to the hoop and cuff by means of a reverse stitch;

Figures 11C-P are highly schematic cross-sectional views of various configurations for attaching a ring to a sleeve;

Figure 12 is a side view of a leaflet having folded portions and an unfolded ventral region that includes a reverse stitch;

Figures 13A-K are highly schematic cross-sectional views of various configurations of attachment of a ring to a deployed leaflet and to a sleeve;

Figure 14 is a side view of a leaflet having folded portions and an unfolded ventral region that includes a rhombus-shaped reverse stitch;

Figure 15 is a side view of a leaflet according to the invention having folded portions and an unfolded ventral region including a pair of parabolic reverse stitches;

Figure 16 is a side view of a leaflet according to the invention having folded portions and an unfolded ventral region that includes a rectangular-shaped reverse stitch; and

Figure 17 is a side view of a leaflet according to the invention having folded portions and an unfolded ventral region that includes a triangle-shaped reverse stitch.

Various embodiments of the present invention are described below with reference to the accompanying drawings. It will be clear that these drawings represent only some embodiments of the invention and therefore should not be considered as limiting its scope.

Detailed description

As used herein, the term "proximal", when used in connection with a prosthetic heart valve, refers to the end of the heart valve closest to the heart when the heart valve is implanted in a patient, while the The term "distal," when used in connection with a prosthetic heart valve, refers to the end of the heart valve furthest from the heart when the heart valve is implanted in a patient. When used in connection with devices for administering a prosthetic heart valve to a patient, the terms "proximal" and "distal" should be taken with respect to the user of the delivery devices. "Proximal" should be understood as relatively close to the user, and "distal" should be understood as relatively further away from the user. Furthermore, as used herein, the words "substantially", "generally" and "approximately" are intended to mean that slight variations from the absolute are included within the scope of the aforementioned structure or process.

Figure 1A shows a typical collapsible prosthetic heart valve 100. The prosthetic heart valve 100 is designed to replace the function of a native aortic valve in a patient. Examples of collapsible prosthetic heart valves are described in International Patent Application Publication No. WO / 2009/042196; United States Patent No. 7,018,406; and US Patent No. 7,329,278. As explained in detail below, the prosthetic heart valve has an expanded condition and a collapsed condition. Although the invention is described herein as applied to a prosthetic heart valve to replace a native aortic valve, the invention is not limited by this fact and can be applied to prosthetic valves to replace other types of heart valves.

The prosthetic heart valve 100 includes a stent or frame 102, which may be formed wholly or partially of any biocompatible material, such as metals, synthetic polymers, or biopolymers that may function as a stent. Suitable biopolymers include, but are not limited to, elastin and mixtures or compounds thereof. Suitable metals include, but are not limited to, cobalt, titanium, nickel, chromium, stainless steel, and alloys thereof, including nitinol. Suitable synthetic polymers for use as a stent include, but are not limited to, thermoplastics, such as polyolefins, polyesters, polyamides, polysulfones, acrylics, polyacrylonitriles, polyetheretherketone (PEEK), and polyaramides. Stent 102 may have a ring section 110, an aortic section (not shown), and an intermediate section (not shown) disposed between the ring and the aortic sections. Each of the ring section 110, the intermediate section, and the aortic section of the stent 102 includes a plurality of cells 112 interconnected around the stent. Ring section 110, middle section, and aortic section of stent 102 may include one or more annular rows of cells 112 connected together. For example, annulus section 110 may have two annular rows of cells 112. When prosthetic heart valve 100 is in the expanded condition, each cell 112 may be substantially diamond-shaped. Regardless of its shape, each cell 112 is formed by a plurality of struts 114. For example, a cell 112 may be formed by four struts 114.

Stent 102 may include commissure features or commissure posts (not shown) that connect at least two cells 112 in the longitudinal direction of stent 102. The commissure features may include eyelets that facilitate suturing of a valve assembly 104 to the stent 102.

The prosthetic heart valve 100 also includes a valve assembly 104 secured within annulus section 110 of stent 102. United States Patent Application Publication No. 2008/0228264, filed March 12, 2007, and United States Patent Application Publication No. 2008/0147179, filed December 19, 2007, describes suitable valve assemblies. Valve assembly 104 may be formed in whole or in part of any suitable biological material, tissue, or a polymer. Examples of suitable biological materials for valve assembly 104 include, but are not limited to, porcine or bovine pericardial tissue. Examples of suitable polymers for valve assembly 104 include, but are not limited to, polyurethane and polyester.

The valve assembly 104 may include a sleeve 106 disposed on the luminal surface of the ring section 110, on the abluminal surface of the ring section, or on both surfaces, and the sleeve may cover all or part of one or both. luminal and abluminal surfaces of the ring section. Figure 1A shows the sleeve 106 disposed on the luminal surface of the ring section 110 to cover part of the ring section while exposing another part of it. In addition to the materials for forming the valve assembly 104 mentioned above, the sleeve 106 and / or any of the sutures described herein may include ultra-high molecular weight polyethylene. Valve assembly 104 may further include a plurality of leaflets 108 that collectively function as a one-way valve.

The cuff 106 of the prosthetic heart valve 100 of Figure 1A tends to experience great stresses and / or deformations in certain areas. In such heart valves 100, the pressure of the blood that the leaflets 108 prevent from flowing into the heart can subject the leaflets 108 to a load in the direction indicated by arrow L, shown in Figure 1B. This load can cause great stress and / or deformation on the cuff and / or leaflets. Also, a typical load can cause wear over time. To manage the increased stress and strain in the cuff 106, some conventional heart valves 100 have thicker cuffs. However, the Thicker cuffs generally lead to a larger heart valve that is more difficult to administer and implant.

One method of redistributing the load has been to attach the leaflets to the struts. Alternatively, it may be advantageous to secure the leaflets substantially completely to the sleeve and not to the struts. In certain procedures, folding valves can be implanted into a native valve annulus without first resecting the native valve leaflets. In addition, other patients may have uneven calcification, bicuspid disease, and / or valve regurgitation.

To reduce adverse cases, (for example, (1) perivalvular leak (PV leak), (2) valve migration, (3) mitral valve impact, (4) conduction system disruption, (5) coronary blockage, etc.) it may be advantageous to perform the sealing and fixing properly without excessive radial force. Embodiments of the present invention that secure the leaflets primarily to the sleeve can achieve better coaptation of the leaflets, reducing the risk of leakage.

Furthermore, the annulus section of the prosthetic valve may have a generally regular cylindrical shape, which means that the structure has a generally circular cross-section with a substantially constant diameter along its length. When placed in the annulus of a native heart valve, such as the tricuspid aortic valve, and expanded, a substantially tight fit should occur. However, the native valve annulus may not be circular and, in fact, may vary from patient to patient, as does the shape of the aortic sinus or aorta, the angle of the junction between the valve annulus and the aortic sinus, and other local anatomical features. When a prosthetic valve is deployed and expanded, it is advantageous to allow for these anatomical variations to function properly. This can cause a distortion of the shape of the stent and / or valve assembly, and repositioning of the leaflets relative to each other, which can affect the coaptation of these leaflets.

Because the stent of a collapsible prosthetic heart valve becomes distorted during implantation, during the heartbeat, or due to irregularities in the patient's anatomy or the condition of the native valve, such distortion can carry over into the valve assembly, thereby so that not all leaflets unite to form effective coaptation junctions. This can cause leakage or regurgitation and other inefficiencies that can reduce cardiac output. Additionally, if the prosthetic valve is not optimally positioned and the valve leaflets do not engage as intended, other long-term effects may be postulated, such as uneven wear of the individual leaflets or increased stress on the cuff. and / or on the stent.

However, prosthetic valves according to certain aspects of the present invention can function properly despite distortion of the stent and / or valve assembly because the leaflets are substantially attached to the sleeve and not to the stent. Without this being an acceptance of any particular theory, it is believed that a valve design with leaflets mostly sewn to the sleeve may be better suited to less than perfect annulus geometry. Such sleeve-leaflet arrangements may be more insulated from geometry-induced imperfect stresses in the struts than those arrangements that have the leaflets entirely or predominantly sewn to the stent. Thus, the possibility of uneven wear due to anatomical variations is greatly reduced by securing the leaflets completely or predominantly to the sleeve.

Furthermore, by sewing the leaflets to the sleeve and not to the struts, greater flexibility is provided for positioning the leaflets and for varying the height, width and shape of the leaflets. Specifically, because the leaflets of conventional heart valves are attached to the struts, the shape and position of the leaflets are limited by the location of the struts. In contrast, suturing patterns can vary with greater benefits when the leaflets are predominantly cuffed.

Having outlined some of the benefits of a leaflet-cuff fixation, the features of this embodiment are described with respect to the prosthetic heart valve 300 shown in Figures 2A-5. It should also be noted that, although the inventions described herein are predominantly explained in terms of a tricuspid valve and a stent having a shape as illustrated in Figures 2A-5, the valve could be a bicuspid valve, such such as the mitral valve, or include more than three leaflets, and the stent can have different shapes, such as a flared or conical annulus section, a less bulbous aortic section and the like, and a differently shaped intermediate section.

In securing the plurality of leaflets, each leaflet 308 may first be attached to stent 302 by suturing through the commissure feature eyelets 316. Additional examples of commissure feature accessories are described in US Patent Application No. Serial No. 13 / 216,124, entitled "Leaflet Suture to Commissure Points for Prosthetic Heart Valve", filed August 23, 2011, published as US2012197391 A1. In addition to commissure features 316, the plurality of leaflets may be attached to sleeve 306 as described below.

Figures 2A, 2B, and 3 illustrate such an embodiment in which leaflets 308 have been secured by suturing them substantially entirely to sleeve 306. In the illustrated embodiment, leaflets 308 are coupled to sleeve 306 after they have been secured. to commissure features 316 However, it will be apparent that those skilled in the art can change or vary the order of attachment as necessary.

Figures 2A and 2B illustrate a sleeve 306 and one or more leaflets 308. Each leaflet 308 includes a proximal end 352 to attach to the sleeve 306 and a free distal end 354 to co-engage with the other leaflets to form a closed valve. As seen in Figure 2A, each leaflet 308 can be folded back on itself at the proximal end 352 to form a ventral fold 356 to secure the leaflet to the sleeve 306. The ventral fold 356 can be formed by bending the proximal end of the leaflet. 308 once upon itself towards the sleeve 306 so that the ventral fold is disposed between a portion of the leaflet and the sleeve. The width x of the ventral fold 356 between the fold line 356a and the free edge 356b can vary from valve to valve, and also within a valve. For example, the ventral fold 356 may have a width x of between about 0.1mm and about 2.0mm. Variants of ventral fold 356 are contemplated herein as well. For example, ventral fold 356 can be formed by folding leaflet 308 more than once (eg, two, three, or more times). In addition, the ventral fold 356 can be formed along only a portion of the proximal end of the leaflet 308 if the entire proximal end to the sleeve 306 is not sutured. Furthermore, the ventral fold 356 can be formed by bending the proximal end of leaflet 308 toward the outside of sleeve 306, rather than toward the sleeve as previously described.

After bending each leaflet 308 to form a ventral crease 356, leaflets 308 may be attached to sleeve 306 according to the fixation pattern shown in Figure 3. For clarity, the leaflet-cuff fixation pattern is described with reference to to Figure 3 without showing a ventral fold. However, it is to be understood that a ventral fold as described above and shown in Figures 2A and 2B may be disposed either on the inner or luminal side of the leaflet 308 or between the leaflet and the sleeve 306.

The prosthetic heart valve 300 of Figure 3 includes a stent or frame 302 having a ring section 310 and an aortic section (not shown). Each of the annulus section 310 and the aortic section of the stent 302 includes a plurality of cells 312 interconnected around the circumference of the stent. Ring section 310 and aortic section of stent 302 may include one or more annular rows of cells 312 connected to each other. For example, annulus section 310 may have two annular rows of cells 312. When prosthetic heart valve 300 is in the expanded condition, each cell 312 may be substantially diamond-shaped. Regardless of its shape, each cell 312 is formed by a plurality of struts 314. For example, a cell 312 may be formed by four struts 314.

Stent 302 may include commissure features 316 that connect at least two cells 312 in the longitudinal direction of the stent. Commissure features 316 may include eyelets to facilitate suturing of a valve assembly 304 to stent 302.

A sleeve 306 may be disposed on the luminal surface of the ring section 310, on the abluminal surface of the ring section, or on both surfaces, and the sleeve may cover all or part of one or both of the luminal and abluminal surfaces of the ring section. Figure 3 shows the sleeve 306 arranged on the luminal surface of the ring section 310 to cover part of the ring section exposing another part of it. In particular, the sleeve 306 covers substantially the entire ring section 310 between the proximal edge of the stent 302 and the commissure features 316, but a much smaller area of the ring section between the commissure features. Valve assembly 304 may further include a plurality of leaflets 308 that collectively function as a one-way valve.

As shown in Figure 3, struts 314a, 314b, and 314c may be connected to each other substantially end-to-end diagonally along three cells 312, beginning with one end of strut 314a connected to a commissure feature 316a and ending with one end of the strut 314c connected to one end of the strut 314d. Struts 314c and 314d are part of the same cell 312a. Struts 314d, 314e, and 314f may be connected to each other end-to-end in a substantially diagonal fashion along three cells 312, beginning with one end of strut 314f connected to a commissure feature 316b and ending with the connection between a strut end 314d and one end of strut 314c. For the sake of integrity, cell 312a includes strut 314c connected to strut 314d at the bottom of the cell and struts 314g and 314h connected to each other at the top of the cell, as well as struts 314d and 314c, respectively. .

In addition to being interconnected around the circumference of stent 302, cells 312 may be interconnected in the longitudinal direction of the stent. Two adjacent struts, for example struts 314e and 314g, merge near the bottom of the cell before separating into two different struts. The meeting point where two struts 314 merge or where a strut splits into two components is defined as an ankon 320. Ancons 320 in two longitudinally adjacent rows of cells 312 may be joined by the sliders r.

The plurality of leaflets 308 may be attached directly to sleeve 306 near struts 314a, 314b, 314e, and 314f, such as by suturing. As shown in Figure 3, the leaflets 308 may be attached to the sleeve 306 just proximally to the aforementioned struts 314 along an attachment line R. Specifically, a distance y may be maintained between the attachment line R and the struts 314. This distance can be greater than, less than or equal to 2.0 mm, and can vary as required. By attaching the leaflets 308 to the sleeve 306 in a pattern that follows the curvature of some of the struts 314, the tension on the sleeve 306 can be reduced while maintaining a degree of flexibility.

As described above, fixation line R includes an initial descent just proximal to commissure feature 316a and continues proximally to struts 314a and 314b while maintaining substantially distance and struts. At the proximal end of strut 314b, fixation line R begins to flatten, passing through cell 312a, and then ascends proximally to struts 314e and 314f, maintaining a distance and substantially the same or similar to the struts, until it reaches a point just proximal to the commissure feature 316b. Between the downward seam and the upward seam, the fastening line may cross a pair of sliders r1 and r2 and form a vertex between them. In at least some other examples, the fixing line R can pass above or below at least one of the sliders r1 and r2.

Figure 4 shows the sliders r1 and r2 in more detail. As previously described, fixation line R descends generally from just proximal to commissure feature 316, travels proximally through struts 314a and 314b, crosses slide r1, changes direction, and crosses slide r2, and it then ascends proximally up struts 314e and 314f until it reaches a point just proximal to commissure feature 316b.

The foregoing discussion describes the general pattern by which leaflets 308 can be directly attached to sleeve 306. After generally describing the pattern of attachment, the following description provides an exemplary method of suturing leaflets 308 to sleeve 306. As will be apparent For persons of ordinary skill in the art, the description that follows is of one of many possible methods, and the distances, configurations and arrangements described are merely exemplary and not limiting. For example, instead of using a single suture around the perimeter of the valve assembly, leaflets 308 can be sutured to cuff 306 using a plurality of sutures, staples, bioglue, or any other suitable attachment method.

Initially, leaflets 308 are aligned with sleeve 306 and struts 314 at desired locations, typically in annulus section 310. The ends of the distal free edge of each leaflet 308 are then sutured to sleeve 306 and stent 302 through of the eyelets of an adjacent pair of commissure features 316. The belly of the leaflets 308 may then be sutured to the cuff 306 around the circumference of the heart valve 300 proximal to the commissure features 316.

Referring to Figure 3, a first leaflet 308 may be sutured to the cuff 306 by first passing a suture from the abluminal side of the cuff 306 to the luminal side of the cuff from about 0.5mm to about 2.0mm proximally of a first feature. commissure 316a. This place is called the origin stitch. A segment of suture tail can be held in the origin stitch to tie to the end of the pattern after sewing has been completed around the circumference of sleeve 306. Leaflet 308 can then be sewn to sleeve 306 using a series of overcasting. In at least other examples, a single or reverse stitch can be used in place of overcasting. The stitches from the abluminal side to the luminal side of the heart valve 300 pass through the cuff 306 only. Stitches from the luminal side to the abluminal side of heart valve 300 pass through both layers of leaflet 308 (eg, leaflet and folded ventral fold 356) and cuff 306. Thus, with each overcast, the suture it is passed from the abluminal side to the luminal side of the heart valve 300 through the cuff 306 only and then through both layers of the leaflet 308 and the cuff 306 from the luminal side of the valve to the abluminal side of the valve.

The stitch spacing and the smallest size may vary. In at least some examples, the stitch spacing and the smallest size can be from about 0.5mm to about 2.0mm, and is preferably about 1.0mm. The stitches can be approximately perpendicular to the edge of the leaflet viewed from the side of valve 300. Starting just proximal to commissure feature 316a, the sutures can be displaced approximately a distance and proximally from struts 314a and 314b, through a first slide r1, forming an apex, through a second slide r2, and approximately at a distance and proximally from struts 314e and 314f until reaching a point just proximal to commissure feature 316b. Sutures may begin at a point A of approximately 0.5 mm to approximately 2.0 mm proximal to commissure feature 316a, and may end at a point B of approximately 0.5 mm to approximately 2.0 mm proximal to the commissure feature 316b.

Thus, between the first commissure feature 316a and the second commissure feature 316b, the suture line R forms a substantially symmetrical parabola. This parabolic pattern can be repeated between commissure features 316b and 316c and between commissure features 316c and 316a around the circumference of cuff 306, ending at or near point A where suture line R began. point A, the end tail of the suture line R can be tied to the origin stitch using a single double knot or any other suitable knot.

Figures 5A and 5B show a comparison between a heart valve 300 according to an embodiment of the present invention and a conventional heart valve 300 '. As will be apparent, the heart valve 300 according to the present invention includes an enlarged cuff 306 that overlaps a portion of the leaflets 308. In contrast, the heart valve 300 'does not include such an overlap between the leaflets 308' and the cuff 306 ' . Rather, leaflets 308 'and sleeve 306' are attached to each other in an edge-to-edge manner. The overlay of the leaflet cuff provided by the heart valve 300 of the present invention forms a pocket P and allows for the suturing pattern discussed above. The pocket P formed by the overlapping of the cuff of the leaflet Minimizes perivalvular leakage and acts as a tissue cushion for increased durability. Compared to conventional devices, this configuration also provides a greater shock absorber against contact wear. Thus, by providing an enlarged cuff, the stress on the cuff can decrease, increase the durability of the cuff, and increase the flexibility of the heart valve to allow applications such as partial deployment of the heart valve, for example, for testing.

In this manner, by attaching the leaflets 308 to the sleeve 306, a number of benefits such as those listed above, as well as others, can be achieved. Furthermore, the above description provides a method by which the stress on the sleeve can be reduced. Specifically, by suturing the leaflets to the cuff, maintaining the space between the suture line and the struts described above, and passing the sutures through the slides, the load on the cuff can be partially redistributed to the struts to avoid possible wear. I fail. Thus, the above embodiment describes a method of reducing stress on the sleeve at critical joints. This method provides a solution by suturing the leaflets to the cuff without providing a thicker cuff or using different materials for the cuff.

Despite the above embodiment, it will be apparent that the leaflets need not only be coupled (except for commissure features) to the sleeve. In other embodiments, instead of suturing the leaflets only to the cuff, selected regions of each leaflet, or the proximal edge thereof, may be secured to a ring disposed on or coupled to the cuff to relieve additional stress on the cuff. These embodiments are described in more detail with reference to Figures 6-11.

Figure 6 is a partial side view of a prosthetic heart valve 600 having a stent 602 and a valve assembly 604 disposed in the annulus section 610 of the stent. Within heart valve 600, leaflets 608 are secured to cuff 606 by sutures. Figure 6 shows a potential cuff-shell clamp load distribution on the valve assembly. When the leaflets 608 are brought together to form a closed configuration, the load is transferred from the leaflet structure to the attachment points along the contour of the leaflet belly. As described in the previous embodiments, these attachment points coincide with the line of attachment R. The load distribution diagram shows that large stitch loads are generated in individual sutures in certain regions L along the line of attachment. A. If the point loads in the L regions are large enough, they pull the suture through the 606 sleeve material. Repetitive wear can pull the suture through the 606 sleeve material. Thus, the L regions can be prone to failure. This failure can occur from tearing the sleeve 606, the leaflet 608, the sutures that secure the sleeve 606 to the leaflet 608, or by any combination of these.

In accordance with the present invention, a suture ring can be attached to the prosthetic heart valve externally to the cuff to redistribute the load at the points where the leaflets are attached to the cuff, reducing the risk of structural damage to the valve due to rupture. in the joint / subassembly formed between the cuff and the leaflet fixation line R. Without being limited to any particular theory, it is believed that the hoop can enhance the durability of the cuff, improve valve function, reduce perivalvular leakage Due to the waviness of the cuff, achieve optimal leaflet contour and help reduce the profile of the implant catheter.

Figure 7A is a highly schematic view of a ring 730 attached to a sleeve 706 in accordance with one embodiment of the present invention. The ring 730 can be formed of a suture, wire, cloth, polymers, reinforced polymers, a metal such as nitinol, a biomaterial such as pericardial tissue, stainless steel or the like, or any combination of these, such as braided wire or a metal-suture combination. In some examples, the ring 730 may be formed of an ultra-high molecular weight polyethylene, such as FORCE FIBER®. Ring 730 may also be formed as a solid rod, tube, or ring to provide fixation in certain portions of sleeve 706. In a specific embodiment, ring 730 can be formed of a nitinol ring that is heat fitted to the meter. of the sleeve 706. As seen in the schematic view of Figure 7A, the ring 730 may be attached to the sleeve with a parabolic guideline that complements the fixing line R. The guidelines and configurations of the ring 730 are explained in more detail below. continuation. It is sufficient from this diagram and the highly schematic diagram of Figure 7B to appreciate that the ring 730 helps to secure the suture between the sleeve 706 and the leaflets 708 by providing a reinforcement to redistribute the load between the leaflets and the sleeve.

Figures 8, 9A and 9B describe various guidelines for attaching the ring to the sleeve. Although these specific attachment guidelines are described herein, it is to be understood that any of the guidelines described above with reference to attachment line R of Figure 3 can be used to attach the collar to the sleeve. The fixation line can be sutured around or through the hoop to provide additional fixation. Furthermore, it is to be understood that the ring may be attached to the sleeve prior to suturing the leaflets to the sleeve. For example, the collar may be attached to the sleeve prior to attaching the sleeve to the stent or after attaching the sleeve to the stent. Furthermore, the ring can be attached to the cuff at the same time that the leaflets are sutured to the cuff.

In a first example, shown in Figure 8, a prosthetic heart valve 800 includes a stent 802 and a valve assembly 804 disposed in annulus section 810 of the stent. A sleeve 806 is attached to stent 802 on the luminal side of ring section 810. Stent 802 includes a plurality of struts 814 connected together to define open cells 812. Struts 814a, 814b, and 814c may be connected to each other substantially diagonally end-to-end along three cells 812, beginning with one end of strut 814a connected to a commissure feature 816a and ending with one end of strut 814c connected to one end of strut 814d. Struts 814c and 814d are part of the same cell 812a. For the sake of integrity, cell 812a includes strut 814c connected to strut 814d at the bottom of the cell and struts 814g and 814h connected to each other at the top of the cell, as well as struts 814d and 814c, respectively. .

Ring 830 may form a pattern around the circumference of sleeve 806. As with the line of fixation R described above, the pattern of ring 830 may also include an initial descent from just the proximal position of commissure feature 816a and it can continue proximally to struts 814a and 814b while maintaining substantially a distance and to struts. At the proximal end of strut 814b, the ring pattern 830 begins to flatten, passing through cell 812a, and then ascends proximally to the next set of struts (not shown in Figure 8), until it reaches a point just proximal. to the next commissure feature. It should be noted that the ring 830 of Figure 8 is attached to the sleeve 806 and is disposed between the sleeve and the stent 802. With this arrangement, the loads from the ring 830 are distributed directly to the sleeve 806 only and not to the struts. 814. In addition, the pattern of the ring 830 in the embodiment of Figure 8 begins and ends at the proximal points of the commissure features 816 as explained.

Figure 9A is a side view of a second example of the attachment of a ring 930 to a cuff 906. The prosthetic heart valve 900 is similar to the prosthetic heart valve 800 described above, and therefore similar elements are identified by numbers from Similar references that begin with the number "9" instead of the number "8". The manner of attachment of the ring 930 is similar to the manner of attachment of the ring 830, with two exceptions. First, the ring 930 is attached directly to the commissure features 916 rather than terminating at the proximal points of the commissure features. Furthermore, ring 930 is disposed toward the outside of stent 902 as shown in the enlarged view of Figure 9B. That is, stent 902 is disposed between sleeve 906 and ring 930. By attaching the ring 930 to the features of commissure 916 and / or by passing the ring 930 out of stent 902, loads can be redistributed from the ring to the stent strut 914.

It is to be understood that any combination of these arrangements can be used to secure the collar 930 to the sleeve 906. For example, the collar 930 may be disposed between the sleeve 906 and the stent 902 as described in Figure 8, but can also be attached to commissure features 916 as described in Figure 9. Alternatively, ring 930 may be disposed toward the outside of stent 902 only at selected points or it may be attached to select commissure features or no commissure features. In this way, the load can be distributed from the ring to the sleeve and / or the stent, as desired.

After describing the manner of fixing the ring to the sleeve and the stent, some possible arrangements for fixing the leaflets to the sleeve and the ring are described below. Various alternatives for such fixation are shown in Figures 10A-C.

Figure 10A is a highly schematic cross-sectional view of a portion of a collapsible prosthetic heart valve 1000 according to an example of the present invention. The heart valve 1000 has leaflets 1008 sutured to both a collar 1030 and a cuff 1006. Each leaflet 1008 may be folded back on itself at its proximal end to form a ventral fold 1056 to secure the leaflet 1008 to the cuff 1006. The ventral fold 1056 may have any of the configurations or arrangements discussed above with reference to Figure 2A or may not include a crease at all. The structure of the heart valve 1000 as described in connection with Figure 10A may be the same for Figures 10B and 10C.

The manner in which the leaflets 1008 are attached to the sleeve 1006 and the collar 1030, as in Figure 10A, is called the "wrapped" configuration. In this wrapped configuration, the leaflet 1008 is folded back on itself to form the ventral fold 1056. A T suture begins from inside the valve 1000 and passes through the leaflet 1008, the ventral fold of the leaflet 1056 and the cuff. 1006. Suture T is then wrapped around loop 1030 and passed into the valve through sleeve 1006 and under the folded edge of leaflet 1008, creating an overcast. This stitch pattern can be repeated around the entire circumference of valve 1000 to secure each of the leaflets 1008 and the collar 1030 to the sleeve 1006.

A second configuration, shown in Figure 10B, is called a "perforated" configuration. In the perforated configuration, suture T begins inside valve 1000 and is passed through leaflet 1008, ventral fold 1056, and cuff 1006. Instead of being wrapped around loop 1030, the suture is perforated through through the ring 1030 and is passed into the valve through the sleeve 1006 and under the folded edge of the leaflet 1008. Obviously, in this embodiment, the ring 1030 must be formed of a material that can receive the suture T through him. This stitch pattern can be repeated around the entire circumference of valve 1000 to secure each of the leaflets 1008 and the collar 1030 to the sleeve 1006.

In a third configuration, the collar 1030 is cinched as shown in Figure 10C. The "snug" configuration can begin similarly to the wrapped configuration of Figure 10A, with the T suture passing from inside the valve 1000 through the leaflet 1008, the ventral fold 1056 and the cuff 1006. The T suture it can then be wrapped in a complete loop around collar 1030 and then passed into the valve through sleeve 1006 and under the folded edge of leaflet 1008. It is to be understood that this configuration The snug fit is not limited to a single loop around the ring 1030, and that the T suture may be encircling the ring 1030 any number of turns, as desired, before passing into the valve interior.

In another configuration, shown in Figures 11A and 11B, the leaflet 1008 is folded over on itself to form the ventral fold 1056 and a reverse stitch B supports the ventral fold 1056 to the leaflet 1008 to create a thickened portion, which then it is coupled to the cuff 1006. The heart valve 1000 has leaflets 1008 sutured to a collar 1030 and a cuff 1006 as shown in Figure 11B. Specifically, a T suture passes through setback stitch B, leaflet 1008, ventral fold 1056, the other side of stitch B, and cuff 1006. The T suture then surrounds loop 1030 and is passed inward. of the valve through the sleeve 1006 and below the folded edge of the leaflet 1008, creating an overcast. This stitch pattern can be repeated around the entire circumference of valve 1000 to secure each of the leaflets 1008 and the collar 1030 to the sleeve 1006. Fold the leaflet 1008 on itself to create a ventral fold and use a reverse stitch. B to secure the two together produces a thickened portion that provides improved structural integrity for securing the leaflet to sleeve 1006 and rim 1030.

Figures 11C-P are highly schematic cross-sectional views of various configurations for attaching the hoop 1030 to the sleeve 1006. As will be apparent from these figures, the suture T can pass through or around any combination of the reverse stitch B, leaflet 1008, ventral fold 1056, cuff 1006 and ring 1030. In addition to these configurations, the ring 1030 can be moved to a different location or multiple rings can be used. For example, a second ring 1030 may be disposed between the leaflet 1008 and the ventral fold 1056 to form the thickened portion in addition to the ring 1030 disposed outside of the sleeve 1006. The ring 1030 can also be disposed within the sleeve 1006 (for example, between cuff 1006 and ventral fold 1056) or in any other suitable position, as long as it helps to redistribute the load on the cuff and helps prevent the cuff from tearing.

In other variations, the ring 1030 may be disposed on the outside of the stent struts in certain portions and within the stent struts at other portions. Ring 1030 may also be woven into and out of sleeve 1006, and may be attached to the commissure features to provide additional fixation. Furthermore, the ring 1030 need not be continuous and can be formed of discrete portions arranged around the circumference of the heart valve.

Although previous configurations have shown a leaflet 1008 folded towards the sleeve 1006 to form a ventral fold 1056, it is to be understood that the leaflet-sleeve assembly, also known as a belly attachment contour, is not limited to this configuration. In other examples, the sleeve-leaflet assembly may include a leaflet that is folded out of the sleeve 1006 to form a ventral crease 1056 on the side of the leaflet 1008 opposite the sleeve. In addition, the leaflet 1008 of the leaflet-sleeve assembly need not form a two-layer ventral fold 1056 at all, but may lie flat against the sleeve 1006. It is further contemplated that the sleeve 1006 itself can be folded and that multiple stitching stitches reverse can be used in place of a single stitch as described above.

As shown in Figure 12, in another embodiment, the leaflet 1208 is folded along only a portion of its belly contour. Leaflet 1208 extends between proximal end 1202 and distal end 1204 and includes a belly 1230 having a free edge 1210 that extends between attachment regions 1212, which mate with commissure features of a stent. A substantially parabolic belly contour 1214 is formed between the attachment regions 1212 on the edge of the leaflet 1208 as opposed to the free edge 1210. The belly contour portions 1214 are folded to form two-layer folded portions 1220. The folded portions 1220 can be formed with any length f1. In one example, the folded portions 1220 each include from about 1/4 to about 1/3 of the length of the contour of the belly 1214. In some examples, the length t1 of each folded portion 1220 is between about 4 mm and about 8mm, and it can be about 6mm. The folded portions 1220 may include the end of the belly contour 1214 that are closer to the attachment regions 1212. Thus, the portion of the belly contour 1214 between the folded portions 1220 can remain substantially flat. By creating an unfolded region spaced from the end of the belly contour 1214, most of the leaflet can be reduced. To reinforce the belly 1230 of the leaflet 1208, which is attached to a sleeve, a reverse stitch B2 can be formed at a distance f2 from the contour of the belly 1214 and can follow the curvature of the contour of the belly. As the stitch B2 extends through the folded portions 1220, it can secure together the two layers that form the folded portions 1220. The backward stitch B2 can end before reaching the free edge 1210 so as not to affect the coaptation of the free edge. 1210 with the free edges of the other leaflets, which collectively form the valve assembly. Therefore, the reverse stitch B2 can be spaced from the free edge 1210 by a distance f3. In at least some embodiments, the distance f3 can be between about 0.5 and about 5mm.

A leaflet having a deployed belly such as that shown in Figure 12 can be coupled to a sleeve in a variety of configurations. Figures 13A-H are highly schematic cross-sectional views of some permutations for attaching a collar 1330 to a sleeve 1306 having a deployed belly. It will be apparent from these Figures, that the T2A-H sutures can pass through or around any combination of reverse stitches B2, leaflet 1308, loop 1330, and sleeve 1306.

In Figure 13A, the T2A suture passes, through the inner reverse stitch B2I, the leaflet 1308, the outer reverse stitch B2O and the sleeve 1306, and finally encircles the hoop 1330 before passing through the sleeve 1306 for a second time and below the edge of the leaflet 1308. Thus, in this configuration, the suture T2A passes through the inner stitch B2I and the outer stitch B2O and surrounds the hoop 1330.

In Figure 13B, the T2B suture passes, through the inside setback stitch B2I and the leaflet 1308, over the outside setback stitch B2O, and through the sleeve 1306, and finally surrounds the hoop 1330 before passing through second time through sleeve 1306 and below the rim of the leaflet. 1308. Thus, in this configuration, the suture T2B passes only through the inside setback stitch B2I and surrounds the outside setback stitch B2O and the hoop 1330.

Figure 13C shows a similar configuration to Figure 13B, except that the T2C suture passes under the outer stitch B2O instead of over it. Thus, in this configuration, the T2C suture passes only through the inside reverse stitch B2I and only surrounds the hoop 1330.

In Figure 13D, the T2D suture passes first inward through leaflet 1308, around interior reverse stitch B2I, and outward through leaflet 1308, under interior reverse stitch B2O and through sleeve 1306, and finally surrounds hoop 1330 before passing through sleeve 1306 a second time. Thus, in this configuration, the T2D suture does not pass through the reverse stitches, it only surrounds the inner reverse stitch B2I and ring 1330, and passes twice through leaflet 1308.

In Figure 13E, the T2E suture passes inward through leaflet 1308, around interior reverse stitch B2I, and outward through leaflet 1308, through exterior reverse stitch B2O and the cuff. 1306, and finally circles ring 1330 before passing through sleeve 1306 a second time. Thus, in this configuration, the suture T2E surrounds the inner reverse stitch B2I and the hoop 1330 and passes through the outer reverse stitch B2O.

In Figure 13F, the T2F suture passes inward through the leaflet 1308, over the inside reverse stitch B2I outward through the leaflet 1308, above the exterior reverse stitch B2O and through the sleeve 1306, and finally surrounds hoop 1330 before passing through sleeve 1306 a second time. Thus, in this configuration, suture T2F surrounds the entire inside back stitch B2I, outside back stitch B2O, and hoop 1330.

In Figure 13G, the T2G suture passes inward through leaflet 1308, through interior reverse stitch B2I, outward through leaflet 1308, over exterior stitch B2O and through the cuff. 1306, and finally surrounds the hoop 1330 and passes a second time through the sleeve 1306. Thus, in this configuration, the T2G suture passes through the inner reverse stitch B2I, and surrounds the outer reverse stitch B2O and the hoop 1330.

In Figure 13H, suture T2H passes inward through leaflet 1308, through interior reverse stitch B2I, outward through leaflet 1308, through exterior reverse stitch B2O, the sleeve 1306 and hoop 1330, and returns by passing a second time through sleeve 1306. Thus, in this configuration, the T2H suture passes through the entire inside reverse stitch B2I, the outer reverse stitch B2O and the hoop 1330, as well as twice through each of the sleeves 1306 and the leaflet 1308.

In Figure 13I, the T2I suture passes inward through the leaflet 1308, under the inner reverse stitch B2I, outward through the leaflet 1308, under the outer reverse stitch B2O and through the cuff. 1306, and finally surrounds loop 1330 before passing through sleeve 1306 a second time. In this configuration, the T2I suture surrounds only loop 1330.

In Figure 13J, the T2J suture passes inward through the leaflet 1308, under the inner reverse stitch B2I, outward through the leaflet 1308, through the outer reverse stitch B2O and the cuff 1306, and finally surrounds hoop 1330 before passing through sleeve 1306 a second time. In this configuration, suture T2J only surrounds hoop 1330 and passes through outer stitch B2O.

In Figure 13K, the T2K suture passes inward through leaflet 1308, under interior reverse stitch B2I, outward through leaflet 1308, over exterior reverse stitch B2O, and through sleeve 1306 , and finally surrounds the hoop 1330 before passing the sleeve 1306 a second time. In this configuration, the T2K suture surrounds the hoop 1330 and the outer stitch B2O.

In addition to these configurations, the ring 1330 can be moved to a different location, or multiple rings can be used. In addition, multiple T2 sutures can be used to engage any combination of cuff 1306, leaflet 1308, reverse stitches B2 and hoops 1330 and can be passed through or around any combination of these elements. Figure 14 shows a leaflet 1408 that is folded only along a portion of its belly contour. Leaflet 1408 extends between proximal end 1402 and distal end 1404 and includes a belly 1430 having a free edge 1410 extending between attachment regions 1412, which engage commissure features as previously described. A substantially parabolic belly contour 1414 is formed between the attachment regions 1412 on the edge of the leaflet 1408 as opposed to the edge free 1410. Two contour portions of the belly 1414 are folded to form two-layer folded portions 1420. To reinforce the belly 1430, which is to be attached to a sleeve, a back stitch B3 can be formed by two segments, B3a and B3b that follow the curvature of the belly contour 1414 at a distance from it in a manner similar to that described with reference to Figure 12. The reverse stitch B3 is formed in a different pattern than that shown in Figure 12. Specifically, the first segment B3a of the reverse stitch B3 has a recurring, substantially diamond-shaped pattern along the contour of the belly of the leaflet. The selected guideline affects load transfer properties, ease of assembly, and bulk. In this case, the pattern of the first segment B3a of the reverse stitch B3 can provide a larger surface to suture within rather than passing through / around a single reverse stitch line.

The first segment B3a of the reverse stitch B3 may end before reaching the folded portions 1420, the layers of which may be secured to each other by a second curved segment B3b or by the reverse stitch B3. Alternatively, the first segment B3a may extend through the folded portion 1420. In addition, the reverse stitch B3 may end before reaching the free edge 1410 so as not to affect the coaptation of the free edge 1410 with the free edges of the other leaflets, which collectively form the valve assembly.

Figure 15 shows an embodiment of the invention of a leaflet 1508 that is folded only along a portion of its belly contour. Leaflet 1508 extends between proximal end 1502 and distal end 1504 and includes a belly 1530 having a free edge 1510 extending between attachment regions 1512, which engage commissure features as previously described. A substantially parabolic belly contour 1514 is formed between the attachment regions 1512 on the edge of the leaflet 1508 as opposed to the free edge 1510. Portions of the belly contour 1514 are folded to form two-layer folded portions 1520. To reinforce the belly 1530, which is to be attached to a sleeve, a reverse stitch B4 can be formed with two complementary second segments, B4a and B4b that follow the curvature of the contour of the belly 1514 at some distance from it. In this embodiment, the segments B4a and B4b of the reverse stitch B4 are not joined together.

The first segment B4a may be substantially parabolic and may terminate before reaching the folded portions 1520. The second segment B4b may follow the contour of the first segment B4b at some distance from it to define a coupling zone 1540 between them to suture the leaflet 1508 to a cuff. The second segment B4b may extend through the folded portions 1520 to secure the two layers of each folded portion to each other. In either case, the reverse stitch B4 may end before reaching the free edge 1510 so as not to affect the coaptation of the free edge 1510 with the free edges of the other leaflets, which collectively form the valve assembly.

Figure 16 shows another embodiment of the invention that is similar to that of Figure 15, except for the reverse stitch pattern B5. The leaflet 1608 extends between the proximal end 1602 and the distal end 1604 and includes a belly 1630 having a free edge 1610 that extends between the attachment regions 1612, and a substantially parabolic belly contour 1614 formed between the attachment regions. 1612 at the edge of the leaflet 1608 as opposed to the free edge 1610. The reverse stitch B5 can be formed by two complementary segments, B5a and B5b that follow the curvature of the contour of the belly 1614 at some distance from it. Segments B5a and B5b of reverse stitch B5 are joined together by segments B5c, thus creating a series of docking rectangles 1650 to receive sutures to couple leaflet 1608 to a sleeve.

The first segment B5a may be substantially parabolic and may terminate before reaching the folded portion 1620. The second segment B5b may follow the contour of the first segment B5b at some distance away from it, and may extend through the folded portions 1620 to ensure the two layers of each portion folded together. Suture 1670 can couple leaflet 1608 to a sleeve via docking rectangles 1650. Specifically, suture 1670 can be passed through the perimeter of a docking rectangle 1650. It may be advantageous to pierce the perimeter of docking rectangle 1650 without piercing the interior of the docking rectangle 1650 more than once and without piercing the belly 1630 in regions outside of the docking rectangle 1650.

Figure 17 shows another embodiment of the invention that is similar to that of Figure 16 except for the reverse stitch pattern B6. Leaflet 1708 extends between proximal end 1702 and distal end 1704 and includes a belly 1730 having a free edge 1710 that extends between attachment regions 1712, and a substantially parabolic belly contour 1714 formed between attachment regions. 1712 at the edge of the leaflet 1708 as opposed to the free edge 1710. The reverse stitch B6 may be formed by two segments, B6a and B6b that follow the curvature of the contour of the belly 1714 at some distance from it.

The first segment B6a of the reverse stitch B6 may include a recurring triangular pattern to accept a suture through it. Suture 1770 can couple leaflet 1708 to a cuff through coupling triangles 1750. Specifically, suture 1770 can be passed through the perimeter of a coupling triangle 1750. It may be advantageous to pierce the perimeter of coupling triangle 1750 without piercing the interior of the coupling triangle 1750 more than once and without piercing the belly 1730 in regions outside the coupling triangle 1750.

During operation, any of the embodiments of the prosthetic heart valve described above can be used to replace a native heart valve, such as the aortic valve. The prosthetic heart valve can be delivered to the desired site (eg, near a native aortic annulus) using any suitable delivery device. During administration, the prosthetic heart valve is disposed within the delivery device in the collapsed condition. The delivery device can be introduced into a patient using a transfemoral, transapical, transseptal, transradial, transaortic, transubclavian, or other percutaneous approach. Once the delivery device has reached the target site, the user can deploy the prosthetic heart valve. Upon deployment, the prosthetic heart valve is expanded into a secure fit within the native aortic annulus. When the prosthetic heart valve has been properly installed within the heart, it functions as a one-way valve, allowing blood to flow in one direction and preventing blood from flowing in the opposite direction.

Although the invention has been described herein with reference to particular embodiments, it is to be understood that these embodiments are merely descriptive of the principles and applications of the present invention. For example, in some embodiments the ring may include certain attachment features, such as tabs for attachment of the heart valve or for implantation in the valve. In at least other embodiments, the ring may include a surface finish or be doped with drugs or other material to ensure ingrowth and sealing of the tissue. Furthermore, while the foregoing discussion has provided examples of folded leaflets, it will be apparent that the leaflet need not be folded and that the heart valve may instead include a belly attachment contour having an unfolded leaflet instead of a folded leaflet.

It will be apparent that the features described in relation to the individual embodiments may be shared with other of the described embodiments.

Claims (7)

1. A prosthetic heart valve, comprising: a stent (302) having a folded condition and an expanded condition, the stent having a proximal end, a distal end, and a plurality of commissure features (316), wherein the prosthetic heart valve further includes; a valve assembly (304) attached to the stent, the valve assembly including a sleeve (306) and a plurality of leaflets (308), each leaflet having a free edge extending between a first end attached to one of the plurality of commissure features and a second end attached to another of the plurality of commissure features, and a second edge attached to the sleeve, the second edge having a first end, a second end, a first folded portion adjacent to the first end, a second folded portion adjacent the second end, and a portion deployed between the first and second folded portions, with the first and second folded portions engaging the leaflet to one of the commissure features; and a backing disposed along the unfolded portion of each of the leaflets, the backing comprising a reverse stitch, the reverse stitch having a recurring triangular pattern. The prosthetic heart valve according to claim 1, wherein the reverse stitch is formed by a substantially parabolic pattern that follows the curvature of the deployed portion. The prosthetic heart valve according to claim 1, wherein the reverse stitch comprises multiple segments and at least one of the segments extends over one of the first folded portion and the second folded portion. The prosthetic heart valve according to claim 1, wherein the reverse stitch is spaced from the free edge of the leaflet. 5. A prosthetic heart valve, comprising: a stent (302) having a folded condition and an expanded condition, the stent having a proximal end, a distal end, and a plurality of commissure features (316), wherein the prosthetic heart valve further includes: a valve assembly (304) attached to the stent, the valve assembly including a sleeve (306) and a plurality of leaflets (308), each leaflet having a free edge extending between a first end attached to one of the plurality of characteristic commissures, and a second end attached to another of the plurality of commissure features, and a second edge attached to the sleeve, the second edge having a first end, a second end, a first folded portion adjacent to the first end, a second folded portion adjacent the second end, and a portion deployed between the first and second folded portions, the first and second folded portions coupling the leaflet to one of the commissure features; and a gusset disposed along the unfolded portion of each of the leaflets, the gusset comprising a back stitch; wherein the reverse stitch comprises multiple segments and at least one of the segments extends over one of the first folded portion and the second folded portion; and wherein the reverse stitch comprises two complementary parabolic curves that define a region of engagement between them to receive sutures. The prosthetic heart valve according to any one of the previous claims, further comprising a reinforcing ring (730) coupled to the cuff. 7. The prosthetic heart valve according to claim 6, wherein the ring forms a repeating parabolic pattern around the circumference of the cuff.